Automatic railroad-brake



A. F. TOULMIN.

Car Brake.

No. 18,715. Patented Nov. 24, 1857.

AM. PHOTOLITHDA'IO. H.Y.(OSBORNE S PROCESS.)

.UNITED STATES PATENT OFFICE.

ALFRED F. TOULMIN, OF ELLIGOTTS MILLS, MARYLAND.

AUTOMATIC RAILROAD-BRAKE.

Specification of Letters Patent No. 18,715, dated November 24, 1857.

To all whom it may concern:

Be it known that I, ALFRED F. TOULMIN,

' of Ellicotts Mills, in the county of Howard,

in the State of Maryland, have invented a new and Improved Mode of Winding Up Without Breaking the Chain Attached to the Brakes of Railroad-Cars, securing a prompt and efiective, yet at the same time gradual, check to the speed of the cars; and I do declare that the following is a full and exact description thereof, reference being had to the accompanying drawings and to the letters of reference marked thereon.

The nature of my invention consists in obtaining by means of a revolving spring axle, connected with the end of a brakechain, a self-regulating process for winding up the brake-chains of railroad cars, avoiding the breaking of the chain by causing the power used to cease before the breaking point of the chain is reached. During the transmission of the power the spring axle offers a resistance to a too violent communication of this power. The brake-chain (which winds itself upon the axle) by the force exerted by the resistance of the wheels to the brakes, draws back the axle from contact with the roller which communicates the power, before the breaking point of the chain is reached. I guard the spring axle from a too sudden check from the tension of the chain, by means of the same springs, which offer a yielding resistance until the axle is freed from contact with the roller. The axle being allowed to play or yield by means of the springs upon which it is hung, performs a double dutyin the first place by moderating the sudden transmission of power, and when the brakechain, having wound itself up upon the axle, draws back the axle by its tension; then in the second place, the springs are brought into use to moderate this tension. The power used to wind up the brake-chain is derived from the revolution of the car or tender wheels, to the axle of which a smaller wheel is attached, moved round by the movement of the axle. This motion or motive power is communicated at pleasure to the axle or rod around which the chain winds, by means of a roller at the end of a handle held by, or moved by the brakesman, (down to communicate, up to free from motion,) said roller moving in its turn a wheel connected with the axle, to which, and around which, the chain fastens or winds; the descent of the handle is more or less, according to the force desired to apply, by using a bolt or aheck intervening, with one or more shoulers.

To enable others skilled in the art to make and use my invention, I will proceed to describe it-referring to the annexed drawings, of which- Figure 1 is a side elevation. Fig. 2 is a bottom view. Fig. 3 is a section. Fig. 4 is an end elevation. Fig. 5 is a perspective view.

Attached to the rod or axle 'A (around which the chain a winds,)are placed springs B B. On to the same axle or rod A I place a wheel (land a cog-wheel F. To the axle X of the car I place awheel D. (corresponding to and opposite to the wheel C, but not touching). Between the wheels C, and D, I place a smaller wheel or roller E, connected to the end of a handle H, which handle H when pressed down forces the roller E against and between the wheels C and D and thus communicates the motion derived from D to the wheel C, and to the axle A (to which the chain a is fastened.) In this way A revolves and winds upon itself the the chain a, connected to the brakes S. S. by means of the opening wedge W. To prevent it from unwinding itself a handle K with a ratchet R catches into the cog wheel F (and when the handle K is raised, of course the chain. is freed and the brakes loosened.)

The wheel D derives its motion from the revolution of the axle X of the tender or car to which it is fastened. When the handle H is at rest its roller E does not touch the wheels D and C, and therefore does not communicate a motion from D to C.

The small wheel or roller E is allowed to descend a certain distance (as greater or less force is desired to be applied) its descent being regulated by the shoulders of the bolt or stop G, which sliding into, or out of, the way of the handle H, gives a greater or less descent to the roller E at the end of the handle H, thereby giving a greater or less power. When the motion communicated to the axle A shall have wound up the chain a the tension upon the chain a will draw back the axle A as far as the springs B B will admit of, but sufficiently far to remove the wheel C, from contact with the roller E, thus at once separating it from the motion derived from the revolution of the Wheels of the tender or car.

I do not claim the application of brakes to railroad cars as new or novel, nor do I claim springs, or ratchet and cog-Wheels as new in Winding up the chain attached to,

brakes to railroad cars. Neither do I claim as my invention the transmission of power derived from the revolution of the car or tender Wheels. But

What I claim as my invention, and desire to secure by Letters Patent, is

"The self-adjusting or self-regulating aetion'of disengaging the revolving spring axle, about Which the brake-chain is Wound up, from further contact with the motive or Winding power, so soon as the brakes are put down sufficiently to offer a great resistance to the progress of the cars, but before the breaking point of the brake-chain is reached; this disengaging being effected by means of the tension from the combination and connection of a revolving springaxle on one end of the brake-chain, and at the-other end the resistance offered to the brakes by the revolution of the car heels, substantially as described.

'ALFRED F. TOULMIN.

Witnesses:

y R. SNoWDEN ANDREWS,

CHARLES S. BRUFF. 

